Phase diagram of the Sm–Dy–Fe ternary system

Abstract The isothermal section at 800°C and vertical sections of SmFe 2 –DyFe 2 and (Sm 0.86 Dy 0.14 ) Fe x (1.6 ≤ x ≤ 2.4) in the Sm–Dy–Fe system were determined by using optical microscopy, X-ray diffraction analysis, electron probe microanalysis, and differential thermal analysis techniques. The isothermal section possesses 6 single-phase regions, 7 two-phase regions, and 3 three-phase regions. There are five intermetallic phases: (Sm, Dy) Fe 2 , (Sm, Dy) Fe 3 , (Sm, Dy) 6 Fe 23 , Th 2 Zn 17 -type (Sm, Dy) 2 Fe 17 , and Th 2 Ni 17 -type (Sm, Dy) 2 Fe 17 . No Sm 6 Fe 23 and (Sm, Dy) 2 Fe 7 phases exist in the ternary system. The vertical section of SmFe 2 –DyFe 2 in the Sm–Dy–Fe system contains 2 single-phase regions, 2 two-phase regions, and 1 three-phase region. Investigation of the vertical section of (Sm 0.86 Dy 0.14 ) Fe x (1.6 ≤ x ≤ 2.4) indicates that it consists of 2 single-phase regions, 5 two-phase regions, and 1 three-phase region.